Projected density field of an evolved FDM halo obtained from the S–P simulation (m_ψ = 10⁻²² eV). From left to right, the panels show the convergence κ_FDM (projected surface mass density relative to the critical density), its elliptical-annular mean 〈κ_FDM〉, and the relative residual between the total and mean convergence (κ_FDM − 〈κ_FDM〉)/〈κ_FDM〉. The ellipticity and position angle of the annuli are inferred from the projected convergence distribution. The white contours correspond to κ_FDM ∼ 0.45 and 0.60, respectively, and highlight the density fluctuations around the critical curve, which is shown in red. For visualization, all maps are clipped at their respective 95th-percentile values. See Section A.4 for further discussion.